Methods and machines for forming cartons



E. J. PLOUGH METHODS AND MACHINES FOR FORMING CARTONS .3 Sheets-Sheet 1 Filed Sept. 28, 1964 y gw/ March 21, 1967 E. J. PLOUGH 3369369 METHODS AND MACHINES FOR FORMING CARTONS Filed Sept. 28, 1964 5 Sheets-Sheet 2 arch 21, 1967 E. J. PLOUGH 9 METHODS AND MACHINES FOR FORMING CARTONS Filed Sept. 28, 1964 3 Sheets-Sheet 5 United States Patent 3,309,969 METHODS AND MACHINES FOR FORMING CARTONS Edwin J. Plough, Wadsworth, Ohio, assignor, by mesne assignments, to Packaging Corporation of America, a corporation of Delaware Filed Sept. 28, 1964, Ser. No. 399,778 16 Claims. (Cl; 9349) This invention pertains to methods and machines for forming cartons and particularly for forming cartons having bellows-type, infolded gussets at their corners.

Carton constructions have long been known wherein a tubular blank is provided with gussets at each of the four corners, and these gussets are pushed inward during the final erection and closing of the carton to form a carton having an octagonal inner enclosure. These cartons are particularly adapted for packaging disc-shaped articles, such as pies. Many products of this type are produced in large quantities at a high production rate on an assemblyline basis, thereby requiring rapid packaging operations. While certain conventional packaging steps in the use of these cartons may be performed with known machines, the gusset folding step has not previously been successfully automated. Thus, prior methods and means for erecting cartons of this type have been largely or entirely manual and have presented one or more serious shortcomings, particularly as applied to high production rate operations. Such shortcomings included slow and cumbersome operations, usually requiring time-consuming, tedious and repetitive manual operations, with resultant high unit costs. For such reasons, gusseted cartons of the type indicated above have not been put to wide usage in packaging high rate-of-production items.

It is an object of this invention to provide methods and machines for use in rapidly and mechanically forming and closing cartons having gussets in one or more walls thereof.

It is another object of this invention to provide methods and machines to facilitate efficiently forming and closing of cartons having gusseted corners.

It is another object of this invention to provide machines adapted to cooperate with other cartonin g machines for automatically forming and closing cartons having corner gussets.

It is another object of this invention to provide machines for cooperating with other continuous-operation cartoning machines for conveniently and efficiently folding gussets in four corners of a tubular blank to form a partially erected carton for closing and sealing by other conventional cartoning mechanisms.

In carrying out this invention in one illustrative form, a tubular carton blank having bellows-fold gussets at the four corners is supported in squared-up condition on a moving conveyor. Spreader means move the end portions of the top and bottom walls of such blank apart to permit movement of the gussets between such top and bottom walls, whereupon folders, carried by said conveyor, push such gussets inward. The spreader means release the top and bottom walls after substantial inward movement of the folders and gussets, and presser bars press the top and bottom walls toward one another to complete the gusset folding operation. Thereafter, suitable end flaps on the blank may be closed and secured in a conventional manner and by conventional means to complete the carton.

For a more complete understanding of this invention, reference should now be had to the example illustrated in the drawings, wherein:

FIG. 1 is a top plan view of a machine employing teachings of this invention, with an erected, partially 3,309,969 Patented Mar. 21, 1967 broken away, tubular carton blank in place between a pair of folders;

FIG. 2 is a vertical cross-sectional view of the mechanism taken along lines 2-2 of FIG. 1, omitting the carton blank;

FIG. 3 is an enlarged top plan view of the folding mechanism of the machine shown in FIG. 1 as it completes folding the gussets of the carton, with the top wall of the cart-on and one folding cam broken away;

FIG. 4 is a right-hand end view of FIG. 3;

FIG. 5 is a perspective view of a tubular car-ton blank for forming a carton having bellows-type gussets at the corners to define an octagonal enclosure;

FIG. 6 is a cross-sectional view of the carton, contents and guides taken generally along line 66 of FIG. 3 and looking in the direction of the arrows;

FIG. 7 is a top plan view of a carton formed on the machine of FIG. 1, with a portion of the top broken away to reveal the contents; and

FIG. 8 is an enlarged elevational view of the rear folders of the machine in FIG. 1.

Referring now to the drawings and more particularly to FIGS. 1 and 2, the illustrated embodiment of the invention comprises a frame 10 on which is mounted two sets of sprockets 12 and 14 to drive a pair of conveyor chains 16, the upper segments of which rest on bed members 18. One pair of sprockets, for instance sprockets 12, may 'be driven by any suitable means such as a motor or a positive drive connection to related machines (not shown) to insure operation of this machine in cooperative timing with such related mechanisms. A pair of folders 20 and 22 are mounted on chains 16 in appropriate spaced relation to receive a squared-up carton blank C therebetween as illustrated in FIG. 1. It is contemplated that a series of such opposed pairs of folders will be mounted on the chains 16, however, only one set is illustrated herein for simplicity and clarity.

The illustrated folders 20 and 22 are designed to assist in the folding of gussets or bellows folds at the corners of the blank C. Referring also to FIGS. 5, 6 and 7, the blank C is a set-up, glued tubular blank including a top wall 24, bottom wall 26, and side walls 28 and 30. A bellows-fold gusset construction is provided at each corner of the blank with each gusset comprising a flap portion 28a or a foldably connected to the respective side wall, and adjacent triangular sections 24a and 26a, each joined along one side to the respective flap portion by a foldline 32 and joined along a second side to the top and bottom walls by foldlines 34, see FIG. 5. Suitable end closure flaps 24b, 26b, 28b, and 30b are foldably connected to the ends of the top, bottom and side walls.

In forming the final carton each gusset flap is folded inward to the position shown in FIG. 7. Each triangular section 24a and 26a is thus folded inward, about the respective foldlines 32 and 34 to a reversed position in back-to-back relation to the respective wall 24 or 26, and provides lateral support for the gusset flaps. Assuming each foldline 34 defines an angle of approximately 22 /2 with the respective foldline 32, each folded gusset will extend inward at an angle of to the respective side wall 28 or 30, see FIG. 7. Thereupon, closing of the end closure flaps completes a carton with an octagonal enclosure, see FIG. 7.

Referring now to FIGS. 1-4 and 8, the folder 20 comprises an L-shaped support 36 which has one leg 36 thereof fixed to the chains 16, and a pair of movable folding wings 38 and 40. The wings are fixedly supported on arms 42 and 44 which in turn are secured to and extend laterally from sleeves 46 and 48. The sleeves are mounted for pivotal movement on posts 50 and 52 which extend transversely from leg 36' of support 36. Operating levers 54 and 56 are also fixed to and extend E3 laterally in an opposite direction from sleeves 46 and 48 and are spaced "longitudinally of the sleeves from arms 42 and 44. The distal ends of levers 54 and 56 carry cam follower rollers 58 and 60. Arms 42 and 44 are biased so as to assume substantially aligned relation by a tension spring 62, the ends of which are secured by pins 63 and 64 to arms 42 and 44, respectively. The spring 62, in this instance, extends around sleeves 46 and 48, as shown, to retain the wings 38 and 40 in their retracted positions as illustrated in FIG. 1. Setscrews 65 carried by levers 54 and 56 are adapted to abut the upstanding leg 36" of support 36 and serve as adjustable stops for the retracted position of wings 38 and 40.

Folder 22 includes the same basic components as folder 20, and like parts of this folder are identified by the same numbers but with a suffix a, see FIGS. 1 and 3. In the illustrated embodiment, folder 22 differs from folder 20 in that its position on chains 16 is reversed and it is spaced from folder 20 by an amount sufficient to permit the tubular blank C to be positioned therebetween. Arms 54a and 56a are angularly oriented with respect to arms 42 and 44, see FIG. 3, whereby rollers 58a and 60a carried on the distal ends of these arms are spaced somewhat further apart than rollers 58 and 60, for purposes to be later noted. Furthermore, a pair of additional arms 59 extend laterally from sleeves 46a and 48a in alignment with arms 42 and 44 and receive adjustable setscrews 65a.

The folders 20 and 22, as aforementioned, are secured to the chains 16 with the vertical legs 36" of the L-shaped supports spaced an appropriate distance to support a squared-up blank C therebetween as illustrated in FIG. 1.

An elongated cam strip 64 is mounted on cross bar 66 and disposed in the path of rollers 58 and 60. A cam plate 68 is secured to the top of cam 64 in the path of rollers 58a and 60a. These cams are of appropriate width with respect to the spacing of rollers 53 and 6t), and 58a and 60a, whereby engagement of the rollers with the cams forcibly spreads the rollers and thereby pivots the folding wings 38, 49, 38a and 40a to their folding positions as illustrated in FIG. 3. Rollers 58a and 60a and the posts on which they are mounted are spaced to clear cam 64, and rollers 58 and 69 pass beneath cam 68 as the folders 29 and 22 are carried through the machine on chains 16.

Adjacent and parallel to the paths of movement of the folders 20 and 22 are a series of guide rods. A pair of short, opposed spreader guides 69 and 70 with converging forward ends 69a and 70a are disposed at each side of the machine to intercept, pass between, and spread the respective end flaps 24b and 26b, see FIGS. 4 and 6. For this purpose, the distance between the uppermost surface of guide 69 and the lowermost surface of guide 70 is somewhat greater than the depth of carton C. Each guide 69 is supported on a plate '72 secured to a stud 74 depending from the crossbar 66, while guides 70 are attached to the underside of plates 78 secured to the frame 10. Another pair of short opposed guides 80 and 82, with diverging forward ends 80a. and 82a, are positioned to the rear and inwardly of guides 69 and 70, to press the end portions of walls 24 and 26 together after the gussets are folded therebetween. The inner opposed surfaces of these guides are spaced apart a distance substantially equal to the depth of the erected carton C. Guides 80 and 82 are secured to studs 84 and 86 which are adjustably supported on crossbars 88 and 99. The length and relative disposition of earns 64 and 68 and spreader guides 69 and '70 along the path of travel of folders 20 and 22, is such that the top and bottom walls of a carton blank C carried between the folders are engaged on spreaders 69 and 70 to prevent collapse of these walls toward one another before the drive rollers of folders 20 and 22 engage cams 64 and 68 to fold the gussets. The spreaders then terminate to release the top and bottom walls while the cams 64 and 68 maintain the folders in the position of FIG. 3. The disposition of the presser guides and 82 relative to cams 64 and 68 is such that the pressers engage the top and bottom wall of the blank C prior to release of the folders by the cams.

Two parallel presser guides 92, provided with upwardly curved forward ends 94, are adjustably supported on crossbars 96 and 98. These pressers are disposed to en gage the upper side of each carton blank C and retain same in a firmly seated position between folders 20 and 22 as the blank is subjected to the gusset folding operation.

In operation, a squared-up carton blank C is positioned between folders 20 and 22 either by hand or by suitable mechanism, for instance by automatic feed from a hopper, or by other suitable mechanism in the packaging system. The product is normally positioned within the squared-up blank prior to placement of the blank between the folders but may be inserted later. As the chains 16 are driven, the folders and blank are moved through the machine (to the left in FIGS. 1 and 2). Presser guides 92 engage the upper surface of the blank and hold same firmly in position on chains 16 between the folders, as guides 69 and 70 engage and spread the end closure flaps 24b and 2617, see FIGS. 4 and 6. These guides support and insure spreading of the walls 24 and 26 from one another as the drive rollers 58 and 60, and 58a and 60a engage the cams 64 and 68, respectively, and drive the folding wings inward to fold-in the fourcorner gussets. The carton blank C then disengages from guides 69 and 70, and passes between presser guides 80 and 82 which press the end portions of walls 24 and 26 together to complete the bellows-type folding of the gussets, and to retain the carton in the resulting folded condition, with the end closure flaps protruding as in FIG. 3. Thereafter, the closure flaps may be closed and secured in any suitable manner to complete and retain the carton in final erected condition as in FIG. 7. This final closing and securing may be performed by conventional machines in accordance with the type of end closure desired and the type of flaps provided. This may be by use of glued flaps, or locking tabs, for instance of the type illustrated, or other known means. This machine may be conveniently integrated with conventional carton end closure apparatus by extending the runs of chains 16 through such apparatus, or by passing the blanks C onto another conveyor, while maintaining the end portions of walls 24 and 26 under compression to retain the gusset folds, for instance by extending pressers 80 and 82.

The method of the present invention is deemed apparent for the aforedescribed operation of the illustrated machine. However, for clarity, it will be appreciated that this method comprises supporting the erected blank C in squared-up condition, spreading and supporting the ends of the walls 24 and 26 to prevent their collapse toward one another as the gussets are pressed inward, then substantially simultaneously pressing in the four gussets from the opposing sides of the carton blank. After the gussets have been folded in a substantial distance, the walls are released from the spreaders, and after the gussets have been folded in sufficiently to move the bellow folds past dead-center (the triangular portions 24a and 26a are past positions normal to walls 24 and 26) the ends of the side walls are pressed toward one another to complete the folding of the gussets and to retain the carton in the resulting partially erected state. The gusset folds are permanently retained by subsequently securing the top and bottom walls together. This is accomplished in closing and securing the end closure flaps of of the blank C.

It will thus be seen that a method and machine have been provided which facilitate rapid automatic folding of cartons having corner gussets. The inventive machines are well adapted to receive carton blanks in a conventional cartoning line, to fold gussets in the cortiers of the blanks, and to present the resulting partially erected blanks in a manner and form well suited for closure by conventional types of end closure mechanisms. While these machines may comprise separate units, they are well adapted for use in cooperative relation with other cartoning machines, and may be in the nature of an attachment to known cartoning machines, or a supplemental unit to be integrated with other machines. The inventive machines are well suited for use with continuous operation cartoning equipment, and for conveniently and efficiently folding gussetsin the corners of tubular blanks.

While particular embodiments of the invention have been shown, it will be understood, of course, that the invention is not limited thereto since modifications may be made by those skilled in the art in light of the foregoing teachings. Therefore, it is contemplated by the appended claims to cover any such modifications as fall within the true spirit and scope of the invention.

I claim:

1. A machine for folding gussets disposed adjacent one end of a tubular carton blank, comprising a conveyor for supporting and moving such blank in one direction, said direction of movement being angularly disposed with respect to the blank gussets, first means operative at a station of travel of the conveyed blank for spreading opposite sides of the blank adjacent the one end thereof, and second means operative at said station for folding the gussets between the spread sides of the blank.

2. A machine as in claim 1 and wherein said first means comprises stationary members having diverging cam surfaces for engaging and spreading such opposite sides of the blank while the latter is being moved in said one direction by said conveyor.

3. A machine for folding gussets disposed adjacent one end of a tubular carton blank, comprising a conveyor for supporting and moving such blank in one direction, said direction of movement being angularly disposed with respect to the blank gussets, first means operative at a first station of travel of the conveyed blank for spreading opposite sides of such blank, folders carried by said conveyor for folding the blank gussets inward between the spread sides, and second means for pressing such spread sides toward one another after release of such sides by said first means and prior to retraction of said folders.

4. A machine for folding gussets disposed adjacent one end of a tubular carton blank comprising a conveyor for supporting and moving such blank in one direction, first means disposed at a station of travel of the conveyed blank for spreading opposite sides of such blank while being moved by said conveyor, and second means carried by said conveyor and operative subsequent to spreading of the sides for folding the gussets inward between such spread sides as such blank is moved by said conveyor.

5. A machine as in claim 4 wherein said folders include a support portion mounted on said conveyor, a pair of wing members pivotally mounted on said support portion and engage-able with the blank gussets, and actuatable means for pivoting said wing members to fold such gussets inward.

6. A machine as in claim 5 and wherein said actuatable means for pivoting said wing members comprises stationary cams along said conveyor, and follower members mounted on said wings and positioned to engage said cams.

7. A machine for folding gussets in carton blanks each having a gusset flap in one wall thereof with bellows panels foldably joined to such gusset flap and to spaced opposed side walls, comprising means for folding such gussets inward between such opposing side walls, and means for preventing collapse of such spaced opposed side walls toward one another, while such gusset flaps are folded between such side walls.

8. A machine for folding gussets in carton blanks each having a gusset flap in one wall thereof with bellows panels in spaced opposed side walls and foldably joined to such gusset flap, comprising means for folding such gussets inward between such opposing side walls, and means for insuring spreading of such side walls relative to one another as such gussets are folded inward between such side walls.

9. A machine for simultaneously folding gussets in opposed side walls of a tubular carton blank between opposing top and bottom walls of such blank, comprising a pair of opposed folders adapted for supporting such a blank squared-up therebetween, each folder including a pivotally mounted member for folding a gusset inward of such blank, first means for pivoting said members, and

' second means for preventing collapse of the top and bottom walls of such blank toward one another adjacent such gussets as said members fold such gussets.

10. A machine for folding gussets in four corners of a carton blank provided with a gusset flap is in a side wall at each such corner thereof and bellows panels in opposing top and bottom walls foldably joined to each such gusset flap, comprising a pair of opposed folders adapted for supporting such a blank therebetween, each folder including a pair of pivotally mounted members for pushing such gussets inward, means spreading such opposing top and bottom walls adjacent such gussets as such gussets are pushed therebetween and releasing such top and bottom walls after substantial inward movement of said members, and means for pressing such top and bottom walls toward one another to retain such gussets in their inwardly folded position.

11. A machine as in claim 10, and including means for actuating said opposed folders substantially simultaneously.

12. A method of forming a carton from a tubular blank having gussets at the corners thereof capable of being folded inwardly between the top and bottom of the blank, said method comprising squaring-up such tubular blank whereby the top and bottom thereof are in spaced substantially registered relation and at least one end of the carton is open, spreading apart the top and bottom of said blank adjacent the corners thereof, folding the gussets inward between the spread top and bottom of said squared-up blank, releasing the spread top and bottom after inward folding movement of the gussets, pressing the blank top and bottom toward one another after such gussets are folded inward past their dead center position, and closing the open end of the resulting carton.

13. A method of forming a carton by machine from an erected, generally rectangular tubular blank having a bellows fold gusset at each corner to be folded inward of such blank between opposing side walls comprising, supporting such blank in squared-up erected form, spreading such opposing side walls, pressing inwardly on all of said gussets of such carton substantially simultaneously to fold such gussets between said opposing sides, and pressing said opposing sides toward one another to retain such gussets in their in-folded position.

14. A machine for folding a gusset provided in a carton blank, comprising a first means for supporting a squared-up carton blank, an adjustably mounted folder positioned to register with a gusset of a blank supported on said first means, and means for effecting adjustment of said folder to fold a registering gusset in a blank so supported.

15. A machine for folding gussets provided in each of four corners of a tubular carton blank, comprising first means for supporting a squared-up tubular carton blank, two pairs of opposed, pivotally mounted, folding members, each of said members being positioned to register with a gusset of a blank supported on said first means, and means for pivoting said folders to substantially simultaneously fold such gussets in the four corners of a blank so supported.

16. A machine for folding gussets provided in each of four corners of tubular carton blanks, comprising a conveyor, a pair of folders mounted on said conveyor for supporting a squared-up tubular carton blank therebetween, each folder including a pair of pivotally mounted folding members, each of said members being positioned to register with a gusset of a tubular blank supported between said folders, and means for pivoting said folding members as said conveyor carries said folding members and a carton blank along the path thereof to fold such gussets in such blank.

References Cited by the Examiner UNITED STATES PATENTS 2,521,996 9/1950 Ray et a1. 2,584,529 2/1952 Allen 53-378 BERNARD STICKNEY, Primary Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,309, 969 March 21, 1967 Edwin J. Plough It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Colum 4, line 50, for "for the" read from the line 69 strike out "of"; column 6, line 19, strike out "is".

Signed and sealed this 26th day of December 1967.

(SEAL) Attest:

EDWARD J. BRENNER Commissioner of Patents Edward M. Fletcher, Jr. Attesting Officer 

4. A MACHINE FOR FOLDING GUSSETS DISPOSED ADJACENT ONE END OF A TUBULAR CARTON BLANK COMPRISING A CONVEYOR FOR SUPPORTING AND MOVING SUCH BLANK IN ONE DIRECTION, FIRST MEANS DISPOSED AT A STATION OF TRAVEL OF THE CONVEYED BLANK FOR SPREADING OPPOSITE SIDES OF SUCH BLANK WHILE BEING MOVED BY SAID CONVEYOR, AND SECOND MEANS CARRIED BY SAID CONVEYOR AND OPERATIVE SUBSEQUENT TO SPREADING OF THE SIDES FOR FOLDING THE GUSSETS INWARD BETWEEN SUCH SPREAD SIDES AS SUCH BLANK IS MOVED BY SAID CONVEYOR. 